CBL enhances breast tumor formation by inhibiting tumor suppressive activity of TGF-β signaling

Casitas B-lineage lymphoma (CBL) protein family functions as multifunctional adaptor proteins and E3 ubiquitin ligases that are implicated as regulators of signaling in various cell types. Recent discovery revealed mutations of proto-oncogenic CBL in the linker region and RING finger domain in human acute myeloid neoplasm, and these transforming mutations induced carcinogenesis. However, the adaptor function of CBL mediated signaling pathway during tumorigenesis has not been well characterized. Here, we show that CBL is highly expressed in breast cancer cells and significantly inhibits transforming growth factor-β (TGF-β) tumor suppressive activity. Knockdown of CBL expression resulted in the increased expression of TGF-β target genes, PAI-I and CDK inhibitors such as p15(INK4b) and p21(Cip1). Furthermore, we demonstrate that CBL is frequently overexpressed in human breast cancer tissues, and the loss of CBL decreases the tumorigenic activity of breast cancer cells in vivo. CBL directly binds to Smad3 through its proline-rich motif, thereby preventing Smad3 from interacting with Smad4 and blocking nuclear translocation of Smad3. CBL-b, one of CBL protein family, also interacted with Smad3 and knockdown of both CBL and CBL-b further enhanced TGF-β transcriptional activity. Our findings provide evidence for a previously undescribed mechanism by which oncogenic CBL can block TGF-β tumor suppressor activity.

A novel disposable, transnasal esophagoscope: a pilot trial of feasibility, safety, and tolerance

A novel disposable transnasal esophagoscope, the E.G. Scan (IntroMedic Co. Ltd., Seoul, Korea), was developed for the evaluation of esophageal diseases while eliminating the inconvenience associated with sterilization, portability, patient monitoring, complications, and the economic burden of sedation. The feasibility, safety, and tolerability of the first version of the E.G. Scan was evaluated in this pilot study. Nasal esophagoscopy was performed successfully in 46 patients with known or suspected esophageal diseases. At least 50% of the Z-line was visualized by the E.G. Scan in 38 (82.6%) of 46 patients. Abnormalities were identified in 27 patients: erosive esophagitis (n=18), Barrett's esophagus (n=1), esophageal varices (n=7), and esophageal candidiasis (n=1). Nasal pain was absent or mild in most patients, and adverse events were not observed. Further technical improvement of the E.G. Scan would increase the diagnostic usefulness in future clinical practice.

Clinical significance of CD151 overexpression in subtypes of invasive breast cancer

Background:

CD151 is a member of the tetraspanin family, which interacts with laminin-binding integrins and other tetraspanins. This protein is implicated in motility, invasion, and metastasis of cancer cells, but the prevalence of CD151 expression in subtypes of breast cancers and its influence on clinical outcome remains to be evaluated.

Methods and results:

The immunohistochemistry-based tissue microarray analysis showed that 127 (14.3%) cases overexpressed CD151 among 886 breast cancer patients. CD151 overexpression was found to be significantly associated with larger tumour size, higher nodal stage, advanced stage, absence of oestrogen receptor and progesterone receptor, and human epidermal growth factor receptor 2 overexpression. CD151 overexpression resulted in poorer overall survival (OS) (P<0.001) and disease-free survival (P=0.02), and stage II and III patients with CD151 overexpression demonstrated substantially poorer OS (P=0.0474 and 0.0169). In the five subtypes analyses, CD151 overexpression retained its adverse impact on OS in the Luminal A (P=0.0105) and quintuple-negative breast cancer (QNBC) subtypes, one subgroup of triple-negative breast cancer (P=0.0170). Multivariate analysis that included stage, subtype, and adjuvant chemotherapy showed that CD151 overexpression was independently associated with poor OS in invasive breast cancer.

Conclusion:

CD151 overexpression may be a potential molecular therapeutic target for breast cancer, especially in QNBC subtype and more advanced stages of breast cancer.

Search for a vectorlike quark with charge 2/3 in t+Z events from pp collisions at √s=7 TeV

A search for pair-produced heavy vectorlike charge-2/3 quarks, T, in pp collisions at a center-of-mass energy of 7 TeV, is performed with the CMS detector at the LHC. Events consistent with the flavor-changing-neutral-current decay of a T quark to a top quark and a Z boson are selected by requiring two leptons from the Z-boson decay, as well as an additional isolated charged lepton. In a data sample corresponding to an integrated luminosity of 1.14  fb(-1), the number of observed events is found to be consistent with the standard model background prediction. Assuming a branching fraction of 100% for the decay T→tZ, a T quark with a mass less than 475  GeV/c(2) is excluded at the 95% confidence level.

MR diagnosis of facial neuritis: diagnostic performance of contrast-enhanced 3D-FLAIR technique compared with contrast-enhanced 3D-T1-fast-field echo with fat suppression

BACKGROUND AND PURPOSE

Current MRI with the CE T1-weighted sequence plays a limited role in the evaluation of facial neuritis due to prominent normal facial nerve enhancement. Our purpose was to retrospectively investigate the usefulness of the CE 3D-FLAIR sequence compared with the CE 3D-T1-FFE sequence in facial neuritis patients.

MATERIALS AND METHODS

We assessed 36 consecutive patients who underwent temporal bone MR imaging at 3T for idiopathic facial palsy. Two readers independently reviewed CE 3D-T1-FFE and CE 3D-FLAIR images to determine the degree of enhancement in each of 5 segments of the facial nerve. We compared AUCs using the Z-test, compared diagnostic performance of 2 MR techniques with the McNemar test, and evaluated interobserver agreement. The Pearson χ(2) test was used for each segment of the facial nerve.

RESULTS

The AUC of CE 3D-FLAIR (reader 1, 0.754; reader 2, 0.746) was greater than that of CE 3D-T1-FFE (reader 1, 0.624; reader 2, 0.640; P < .001). The diagnostic sensitivities, specificities, and accuracies were 97.2%, 86.1%, and 91.7%, respectively, for CE 3D-FLAIR, and 100%, 56.9%, and 78.5%, respectively, for CE 3D-T1-FFE. The specificity and accuracy of CE 3D-FLAIR were greater than those of CE 3D-T1-FFE (specificity, P = .029; accuracy, P = .008). The interobserver agreements for CE 3D-FLAIR (κ-value, 0.831) and CE 3D-T1-FFE (κ-value, 0.694) were excellent. Enhancement of the canalicular and anterior genu segments on CE 3D-FLAIR were significantly correlated with the occurrence of facial neuritis (P < .001 for canalicular; P = .032 and 0.020 for anterior genu by reader 1 and reader 2, respectively).

CONCLUSIONS

CE 3D-FLAIR can improve the specificity and overall accuracy of MR imaging in patients with idiopathic facial palsy.

P3-14-18: Primary Tumor Response to Neoadjuvant Chemotherapy Is Significantly Associated with Nodal Pathological Complete Response in Breast Cancer Patients with Cytologically Proven Axillary Node Metastasis

Background: Axillary node status is the most significant factor for the prediction of outcome in breast cancer patients whether they received neoadjuvant chemotherapy or not. However, a reliable method to predict nodal response to neoadjuvant chemotherapy is not established yet. The aim of this study was to identify the predictive factors of axillary pathological complete response (pCR) after neoadjuvant chemotherapy in breast cancer patients with cytologically proven axillary lymph node metastases.

Patients and methods: A total of 123 patients with axillary metastases confirmed by ultrasound-guided fine-needle aspiration biopsy were subsequently treated with four cycles of anthracycline (60mg/m2) plus cyclophosphamide (600mg/m2) followed by doxetaxel (75-100mg/m2) between August 2008 and March 2011. After neoadjuvant chemotherapy, all patients underwent a definite breast surgery with complete axillary lymph node dissection. Clinicopathological parameters were evaluated using a chi-square test and logistic regression model in association with node pCR.

Results: The mean age at diagnosis was 47.9 years in all patients. Eighty-one (65.9%) patients were preoperative clinical T2 stage, 74 (60.2%) showed estrogen receptor (ER)-positivity, and 36 (29.3%) demonstrated HER2−positivity. A pCR of the axilla and breast was determined in 56 (46%) and 40 (31.7%) patients, respectively. Breast Pcr rate is significantly associated with age≤50 at diagnosis, ER(−),PR(−) and higher Ki-67 proliferation. Axillary pCR rate is significantly associated with age at diagnosis of 50 or less, smaller primary tumor size at diagnosis, tumor responsiveness to neoadjuvant chemotherapy, estrogen hormone receptors-negativity, higher Ki-67 proliferative index at diagnosis, and subtypes of HER2−enriched or triple negative breast cancer. When these factors entered logistic regression model, tumor response( SD+PD vs CR+PR: OR 8.603, P=0.007), Ki67((−) vs (+): OR 7.157, p=0.009), ER status((+) vs (−) : OR 4.943, P=0.036), pre-operation tumor size(&gt;2cm vs ≤2cm: OR 5.116, p=0.044), HER2 status( (−) vs (+): OR 5.029,p=0.046) remained to be significant for the prediction of axillary pCR, favorable nodal response.

Conclusion: Our study suggests that primary tumor response to neoadjuvant chemotherapy is significantly associated with favorable nodal response. The factors of tumor and nodal response were similar. There are many issues remained to be determined yet.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-14-18.

P4-09-35: Co-Expression of Ki-67 Is Critical for Outcome of Cyclooxygenase-2 Positive Breast Cancer

Background

The purpose was to investigate the implications of cyclooxygenase-2 (COX-2) and Ki-67 expression on the progression and prognosis of breast cancer.

Methods: COX-2 and Ki-67 levels were immunohistochemically determined using tissue microarrays of 1,028 breast tumors treated between November 1999 and August 2005. COX-2 and Ki-67 levels were compared by tumor progression and clinicopathological parameters were investigated in association with both markers status which was divided into 3 subgroups: COX-2(+)/Ki-67(+), COX-2(+)/Ki-67(−), COX-2(−)/Ki-67(any).

Results: COX-2 expression was significantly higher in intraductal carcinoma and progressively decreased in small T1 lesions and then in T2-T4 tumors, but Ki-67 was significantly expressed at high levels in T2-T4 lesions than in intraductal or T1 carcinomas. COX-2 expression was positively associated with favorable parameters such as older age at diagnosis, smaller size, well-differentiation, hormone receptor-positivity, and was inversely associated with Ki-67 expression. Among 816 invasive tumors, COX-2 expression alone was not related to outcomes. In combination with Ki-67 expression, however, COX-2(+)/Ki-67(−) tumors were significantly associated with favorable characteristics including HER2−negativity and demonstrated favorable outcomes. COX-2(+)/Ki-67(+) tumors showed unfavorable factors and the worst outcomes. COX-2(−)/Ki-67(any) subgroup presented intermediate prognosis. Statistical significance of COX-2 combined with Ki-67 was maintained in Cox's models adjusting for clinicopathological parameters among not only whole population but also ER-positive subgroup.

Conclusions: Our study suggests that COX-2 is expressed in early phase of breast cancer development and is associated with favorable prognostic markers. But co-expression of high Ki-67 proliferative index could indicate an aggressive phenotypic change in COX-2 positive breast cancer. The mechanisms should be further investigated.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-35.

Simultaneous grayscale and subharmonic ultrasound imaging on a modified commercial scanner

OBJECTIVE

To demonstrate the feasibility of simultaneous dual fundamental grayscale and subharmonic imaging on a modified commercial scanner.

MOTIVATION

The ability to generate signals at half the insonation frequency is exclusive to ultrasound contrast agents (UCA). Thus, subharmonic imaging (SHI; transmitting at f(0) and receiving at f(0)/2) provides improved visualization of UCA within the vasculature via suppression of the surrounding tissue echoes. While this capability has proven useful in a variety of clinical applications, the SHI suppression of surrounding tissue landmarks (which are needed for sonographic navigation) also limits it use as a primary imaging modality. In this paper we present results using a commercial ultrasound scanner modified to allow imaging in both grayscale (f(0)=4.0 MHz) and SHI (f(0)=2.5 MHz, f(0)/2=1.25 MHz) modes in real time.

METHODS

A Logiq 9 ultrasound scanner (GE Healthcare, Milwaukee, WI) with a 4C curvilinear probe was modified to provide this capability. Four commercially available UCA (Definity, Lantheus Medical Imaging, North Billerica, MA; Optison, GE Healthcare, Princeton, NJ; SonoVue, Bracco Imaging, Milan, Italy; and Sonazoid, GE Healthcare, Oslo, Norway) were all investigated in vitro over an acoustic output range of 3.34 MPa. In vivo the subharmonic response of Sonazoid was investigated in the portal veins of four canines (open abdominal cavity) and four patients with suspected portal hypertension.

RESULTS

In vitro, the four UCA showed an average maximum subharmonic amplitude of 44.1±5.4 dB above the noise floor with a maximum subharmonic amplitude of 48.6±1.6 dB provided by Sonazoid. The average in vivo maximum signal above the noise floor from Sonazoid was 20.8±2.3 dB in canines and 33.9±5.2 dB in humans. Subharmonic amplitude as a function of acoustic output in both groups matched the S-curve behavior of the agent observed in vitro. The dual grayscale imaging provided easier sonographic navigation, while the degree of tissue suppression in SHI mode varied greatly on a case by case basis.

CONCLUSIONS

These results demonstrate the feasibility of dual grayscale and SHI on a modified commercial scanner. The ability to simultaneously visualize both imaging modes in real time should improve the applicability of SHI as a future primary clinical imaging modality.